The present invention relates to the fields of downhole oil, gas, and/or geothermal exploration and more particularly to the fields of expandable tools for downhole exploration. The prior art discloses expandable tools used to enlarge the diameter of a wellbore during drilling operations. Expandable tools of this type may contain blades which extend from the sides of a drill string and contact the well bore wall.
U.S. Pat. No. 7,314,099 to Dewey et al., which is herein incorporated by reference for all it contains, discloses an expandable downhole tool comprising a tubular body having an axial flow bore extending there through, at least one moveable arm, and a selectively actuatable sleeve that prevents or allows the at least one moveable arm to translate between a collapsed position and an expanded position. A method of expanding the downhole tool comprises disposing the downhole tool within the wellbore, biasing the at least one moveable arm to a collapsed position corresponding to an initial diameter of the downhole tool, flowing a fluid through an axial flow bore extending through the downhole tool while preventing the fluid from communicating with a different flow path of the downhole tool, allowing the fluid to communicate with the different flow path by introducing an actuator into the wellbore, and causing the at least one moveable arm to translate to an expanded position corresponding to an expanded diameter of the downhole tool.
U.S. Patent App. 2008/0128175 to Radford, et al., which is herein incorporated by reference for all that it contains, discloses an expandable reamer apparatus for drilling a subterranean formation including a tubular body, one or more blades, each blade positionally coupled to a sloped track of the tubular body, a push sleeve and a drilling fluid flow path extending through an inner bore of the tubular body for conducting fluid there through. Each of the one or more blades includes at least one cutting element configured to remove material from a subterranean formation during reaming. The push sleeve is disposed in the inner bore of the tubular body and coupled to each of the one or more blades so as to effect axial movement thereof along the track to an extended position responsive to exposure to a force or pressure of drilling fluid in the flow path of the inner bore.